Mobogenie updates vs Play Store

I've installed a program called Mobogenie which I thought is kinda an alternative to the play store and it looks cool for me except that I'm frustrated by the fact that Mobogenie informs me of several updates to many apps on my cell but when I click the update button of a particular app, I'm re-directed to the app's page on play store which still have the old version (because I only have an "open" button to open the app from there rather than an "update" button) so what's the deal?